Oxygen delivering apparatus of the demand type



Feb. 2, 1943. J. A. HEIDBRINK 2,310,022

OXYGEN DELIVERING APPARATUS OF THE DEMAND TYPE Filed April 10, 1941 SYSheetS-Sheet 1 F 1943- J. A. HEIDBRINK 2,310,022

OXYGEN DELIVERING APPARATUS OF THE DEMAND TYPE Filed April 10, 1941 3 Sheets-Sheet 2 '79 Fig-3 we 9 4 26 29 g-' Q G as C) '0 a? U l a A (3 s E U 6 L.|

9| f Q Q 'n '8 27 65 53 "l I I02 Ru 4 7 2R1 2s 7-214: 2G 58 5 F1375 g 42 40 34- :I as 28 i 85 as .3 i I 86 9| 9 38 ii:

96 2 A H 36 99 107 v 5 z g 5 92 lg 98 94 35 i 1: 87 :V: I I 953 39 I 2 4| g I 43 I 1' A 44 es F19r4 InvenL'o r.-

Feb. 2, 1943.

J. A. HEI'DBRINK OXYGEN DELIVERING APPARATUS 0F THE DEMAND TYPE Filed April 10, 1941 3 Sheets-Sheet 3 Inventor J'ouj fl: Heicillor-ir nk. firfo neg.

Patented Feb. 2, 1943 DEMAND T YPE Jay A. Heidbrink, Minneapolis, Minn., assignor to Air Reduction Company, Incorporated, New York, N. Y., a corporation of New York Application April 10, 1941, Serial No. 387,936

9 Claims.

My invention relates to oxygen delivering apparatus of the demand type and has for its object to provide apparatus to be worn by pilots, aviators and others at altitudes so high that it is necessary to supply added oxygen to such wearers.

It has been common practice to provide in conjunction with a mask worn by such persons, means including a rebreathing compartment and tube connections thereto for delivering to the breathing line a constant stream of oxygen and for adding to said stream at inhalation a certain percentage of external air, exhalations going first to refill the rebreathing compartment and then escaping to atmosphere.

It has been found that at great heights and in the severe cold which is there encountered it may be undesirable to inhale external air for the reason that it tends to cool the gases going to the lungs to an excessive degree and to produce freezing of the inlet'air valve. Also, where the breather is under surrounding conditions of abnormal barometric pressure or where those conditions change rapidly as in the rapid ascent or descent of an airplane, exclusion of nitrogen from the lungs will prevent pathological disturbances which sometimes result in what is known as the bends. For these reasons under certain conditions it has been found advantageous to provide means whereby inhalation draws in oxygen only, exhalation taking place as before, first to refill the rebreathing compartment and then to discharge to atmosphere the last of exhaled gases, which are those most heavily charged with carbon dioxide. And for carrying out this latter method I have discovered that better results are obtained by having intermittent delivery of the oxygen upon inhalation only and of a volume suflicient to meet any demand of the person so inhaling, that is, to supply oxygen as demanded by the inhalation capacity of the individual wearing the apparatus.

It is, therefore, a principal object of my invention to provide apparatus having an inhalation circuit closed to external airin combination with a rebreathing compartment and means associated with the rebreathing compartment whereby when the same'is emptied by-the early part of an inhalation, valve mechanism will operate to permit inlet of oxygen to complete the full respiration.

It is a further object of my invention to provide a special type of rebreathing and reservoir compartment which embodies a metal casing and a.

folded flexible sheet sealed within said metal casing, which upon exhalation will move to the top of the compartment, expanding it to full capacity for holding a maximum volume of exhaled gases and which upon inhalation will movein the opposite direction under atmospheric pressure and will actuate the long arm of a twoarmed lever, thereby opening the oxygen valve until the demands of the wearer for a full inhalation are satisfied by resulting inflow of oxygen.

It is a further object of my invention to provide means for supporting the aforesaid rebreathing compartment under the coat of the aviator where it will not be subject to severe external cold and to conduct the oxygen to the metal casing rebreathing compartment under said coat.

It is a further object-of my invention to provide protected exhaling valve means which may be positioned adjacent the metallic casing of the prevent freezing.

The full objects and advantages of my invention will appear in connection with the detailed description thereof and the novel features by which those advantages are secured will-be particularly pointed out in the claims.

In the drawings: h

Fig. 1 illustrates the oxygen supplying apparatus as worn, viewed from the side.

Fig. 2 is a plan view of that part of the oxygen delivering apparatus which is worn under the coat with some parts broken oil.

Fig. 3 is an end view of a part of the apparatus taken on line 3-3 of Fig. 2.

Fig. 4 is an enlarged sectional view taken on line 4-4 of Fig. 3 as the apparatus is positioned when beneath-the coat of the wearer.

Fig. 5 is an enlarged sectional plan view taken through the oxygen valve mechanism and a part of the rebreathing compartment along the line indicated at 5-5 of Fig. 6.

Figs. 6, 7 and 8 are transverse sectional views of the rebreathing compartment and parts of the valve mechanism taken on line 6-6 of Fig. 2, with the rubber sheet in different positions due to exhalation and inhalation respectively.

Fig. 9 is a sectional view showing themask connector T and the means of attachment of the exhaling valve when the same is external to the coat of the wearer.

Referring to Fig. l, a mask I8 of suitable construction is secured by means of a band upon the face of the wearer. This mask is provided with a turret 2 in which is located a microphone (not shown), said microphone being directly in front of the mouth of the wearer. The mask is provided with a tube I3 which extends from the lower center of the mask body at an outward angle, as shown in Fig. 1. This tube has applied thereto a connector member I4 which is shown in detail in Fig. 9. It comprises a connector tube I5 held within outlet tube I3 and extension tubes I6 and I1 at right angles thereto in the form of a T, which receives the ends I8 and I9 of two extension tubes 28 and 2|; These tubes will preferably be corrugated, as shown, although uncorrugated or smooth tubes may under certain conditions be employed. The union member I4 also is provided with a threaded opening 22, Fig. 9, which may receive the exhaling valve 23 as shown in Fig. 9 or may be closed with a cap 24', as indicated in Fig. 1, when it is desirable to have the exhaling valve positioned under the coat of a wearer.

As best shown in Figs. 2, 4 and 5, the rebreathing compartment comprises a metal casing 24 circular in cross section provided with a bottom 25, cylindrical wall 26 and a perforated cover 21, the perforations being a series of round openings 28, as clearly shown in Fig. .2. As shown in Fig. 4, the cover 21 is provided with a flange 29 which grips between it and the cylindrical wall 26 the edge 38 of a sheet of flexible rubber 3|. This sheet of rubber is folded upon itself as indicated at 32, Fig. 4, and has a portion 33 of its body engaging a flat disc lever 34 which is secured to a bar 35, Figs. 6, '7 and 8. The bar 35 has an upstanding arm 36 mounted on a pintle 31 pivoted in ears 38, 39 on the angle posts 48, 4| which are secured by screws 42,- 43 upon being of Bakelite, as indicated. Extension 5| has formed on its top a Bakelite cap 52 which has an annular flange 53 adapted tosurround the tube 5| over a gasket 54 at the end of tube 5|, and to be held in position by apost 55 screwed 'into casting 41 at 56 and threaded at 51 into an extension nut 58 fast on cap 52. A thumb piece 59 enables the partsto be brought into rigid gas-tight relation.

As shown in Fig. 3, the cap 52 is provided withopposite extensions 68 and 6| each having an annular rib 62 for receiving the ends 63 and 64 of tubes 28 and 2 I. These tubes are thus readily attached and detached from the extensions Gil-and 6|. These wing extensions open through cap 52 into chamber 58, as indicated at 65 in Fig. 4.

By these means, as will be apparent from the drawings and the foregoing descriptiomthe rebreathing compartment 66 within the casing 24 is put in free communication with the mask and thepassages leading therefrom.

The exhaling valve, indicated in Fig. 9 as positioned externally upon the union member I4, may be conveniently attached to the extension 5| directly opposite the opening 46 from rebreathing compartment 66, as shown in Fig. 4. This figure illustrates that a base member of Bakelite 61' on castings 61 has a boss 68 thereon threaded into a boss 69 on the member 41. The boss 68 has an internal chamber 18 (Fig. 4) in communication with the chamber 58 within tubular extension 5|. The chamber I8 has formed thereon a valve rim or edge II which has held in engagement therewith a valve disc 12 by means of a spring 13 surrounding a fixed post 14 having thereon a pin 15 on which the valve disc 12 is adapted to move back and forth.

Openings 11 communicate past valve disc 12 with chamber 18 for permitting exhalation to pass after the rebreathing compartment 66 has been fllled and suflicient pressure is built up to overcome the force of spring 13 engaging valve disc 12. The parts are held assembled in position byvmeans of a cap 18 (Fig. 4) threaded on to the end of tubular casting 61. Surrounding the Bakelite casting 61 is a heavy cap member I9 which is threaded upon the casting 61, as clearly shown in Fig. 4, leaving an annular chamberor space 88 between the inner cylindrical wall of the cap and the outer cylindrical wall of casting 61. The annular chamber 88 opens into a flat cylindrical chamber 8|, over cap 18 and communicates with an opening 82 through which the gases of exhalation may pass. It will'be understood that valve structure 23 is identically the same in Fig. 9 as in Fig. 4, the parts being differently sectioned in the latter figure.

Oxygen is supplied from a tank with suitable pressure regulator means (not shown) through a tube 83 which, as shown in Fig. 5, surrounds a nipple 84 leading to a valve chamber 85. Valve chamber 85 is formed within a pair of casting members 86 and 81 screwed together at 88 upon a gasket 89' forming an air-tight seal. The member 81 is in turn threaded at 98 into the casting block 44 with a sealing gasket 9| between portions of member 81 and block 44. A

guide 92 for valve stem 93 is secured in position by means of a nut 94 threaded into the piece 61. The nut 94 is provided with a valve seat 95, and passages 96 surround the stem 93. Upon the stem 93 is a valve disc 91 which is urged against the valve seat by a spring 98 within the valve chamber 85, thus normally sealing that chamber against passage of gas through air passages 96 into the rebreathing compartment 66.

It will be noted from Figs. 5 and 8 that the 4 short arm 36 of lever 35 has thereon a ball 99 which engages the face of end I88 of valve pin 93. The actual thrust lever arm of this lever system is therefore the distance between the axial center of pin 31 and the point of contact of ball 99.

The container 24 is formed at its bottom with a depression |8| (Fig. 4) carrying a tubular member |82 which is sealed into the cylindrical wall 26. The member I82 is closed by a rubber cap I83. This is a container for condensate from the breath. and the operator can from time to time withdraw the rubber cap I83 to let the accumulated moisture run out. In pracice I may carry a rubber band I84. Figs. 2 and 4, about the tubular member I02 and across the top of cover member 21 and about the tube extension 5|, as indicated at I85 in Fig. 4, which would have the effect of aiding in holding the cover 21 in position. a

which the tube member will extend while.

the apparatus is being worn. The tubes 20 and 2| will extend normally, as indicated in Fig. 1, to the mask structure as worn and the assemblage will be held in position for use.

dicated' in Fig. 8, and pressure built up toovercome the force of the spring I3 in the exhaling valve, that will open permitting the remainder of the expiration Y which contains the larger proportion of carbon dioxide to escape to atmosphere. This operation will take place in the same way whether the exhaling valve 23 is outside the coat, at a distance from the rebreathing compartment, as indicated in Fig. 9, or is within the coat immediately adjacent the rebreathing compartment, as in Fig. v4.

Upon inhalation the rebreathing compartment 66 will first be substantially emptied until,

be caused to surround the body ofthe valve 7 toward the point'of escape of exhalation gases to atmosphere and thus keep that body warm so that there will be little or no chance of freezing. And in either the position of Fig. 9 or the position of Fig. 4 any condensation in the exhaling valve will readily escape, in the arrangement in Fig. 9 directly to atmosphere, in the arrangement of Fig. 4 back into the passages I0, 49 and through the opening 46 to. the drip collector I02.-

These are the advantages of this invention which are very obvious from the description and mode of operation outlined above. It may be noted that the double anchorage formed by the tubes 20, 2| between the mask I0 andthe tubular extension 5| extending through the coat at I08 will aid in preventing any lift of the mask during rapid descent such as takes place with dive bombing, since the extension 5| extending through the opening I08 in the coat cannot yield and the tubes 20 and 2| will not be readily torn loose.

A further advantage of my invention is to be found in its adaptability to be employed in connection with a fully closed breathing circuit. For this purpose a soda lime container of known form and well understood use (not shown) may be applied in the connection 41 between the easing wall 25 and the tube 50, and the exhaling valve may be entirely out out so that breathing will pass through the soda lime container either on the inhaling breath alone or on both inhaling as indicated in Fig. 6, the front flap 33 of the flexible closure 3| will have been brought into engagement with the face of disc 34 forming part of long lever arm 35. Continued inspiration will cause the flexible container to further expand under pressure of external atmosphere with the result that the long lever arm'is rocked to the position of Fig. 7 and the valve disc 91 is pushed out against the pressure of spring 98 to open the valve-and permit oxygen to move through and around the outer portions of flexible container 3| to opening 46, whence it .passes to the lungs of the breather in a volume suflicient to meet the demands of a complete normal inspiration.

This cycle will be repeated continuously in natural breathing, whereby the aviator, observer or .other occupant of the plane at high altitudes will be constantly breathing an atmosphere of pure oxygen, only diluted to some extent by water vapor and carbon dioxide, the latter acting in a well-known way to stimulate breathing. The oxygen passing into the rebreathing compartment which is under the heavy-coat and and exhaling, all in a well-known manner. By these means the combined expansible reservoir rebreathing compartment and the demand type oxygen inlet valve mechanism may be employed in connection with completely closed circuit administration of oxygen.

I claim:

1. A device for administering oxygen and excluding nitrogen comprising a mask, a rebreathing compartment having gas-flow connection with the mask, said compartment comprising a rigid shell having parallel face walls, a perforate cover and a flexible sheet held gas-tight upon the edges of the shell by the cover said sheet being folded upon itself, so that on exhalation it will contact one of said face walls and upon inhalation it will substantially contact the other of said face walls, said connection between the mask and the rebreathing compartment opening from the latter below said flexible sheet.

2. A device for administering oxygen and excluding nitrogen comprising a mask, a rebreathing compartment having gas flow connection with the mask, said compartment comprising a rigid shell having parallel face walls, a perforate cover and a flexible sheet held gas-tight upon the edges of the shell by the cover said sheet being folded upon itself, so that on exhalation it will contact one of said face walls and upon inhalation will be moved by external air pressure to contact the other of said walls, an oxygen valve, and means within said compartment subject to the action of said flexible sheet when the compartment is emptied by an inhalation to effect operation of the valve to permit flow of oxygen into and from the rebreathing compartment as long as inhalation continues.

3. A device for administering oxygen and excluding nitrogen comprising a mask, a rebreathing compartment having gas-flow connection with the mask, said compartment comprising a rigid shell, 9. perforate cover and a flexible sheet ment is filled with exhalation gas and may move toward contact with the bottom of the compartment upon inhalation, an oxygen control valve, and means actuated by the last stated movement of said flexible sheet for operating the'valve to permit flow of oxygen into and from the 'rebreath- 7 ing compartment as long as inhalation continues.

4. In a device for administering oxygen at high altitudes, a rebreathing compartment comprising a rigid shell, a perforate cover, a flexible sheet removably sealed within the shell by the perforate cover, said flexible sheet being folded upon itself so that the same may be pushed against the perforate cover by exhalation and will be caused to move toward contact with the bottom of the compartment upon inhalation, a tubular connector member secured to a side of the shell and opening thereinto beneath the flexible sheet, said connector being adapted to pass through an open-- ing in the coat of a-wearer, a mask and tubes adapted to extend outside the clothing from the connector to said mask.

5. In a device for administering oxygen at high altitudes, a rebreathing compartment comprising a rigid shell, a perforate cover, a flexible sheet removably sealed within the shell by the flexible cover, a tubular connector member secured to a side of the shell and opening thereinto beneath the flexible sheet, said connector being adapted to altitudes, an exhaling valve comprising a casing formed with an inner valve chamber, a valve inside the chamber adapted to open upon exha1ation, a second casing member surrounding the casing forming the valve chamber to leave a second chamber around and at the top of said valve chamber casing, said second chamber opening to atmosphere adjacent its top, and openings from the valve chamber into the second chamber,

whereby the valve chamber will be maintained warm by exhalation passing around the same and freezing of the valve will be prevented.

7. A device for administering oxygen and excluding nitrogen comprising a rebreathing compartment formed of a rigid "shell'having parallel face Walls, aflexible sheet folded upon itself-and held'gas-tight about its edges adjacent one of said walls, said sheet being folded upon itself so that on exhalation it'will contact one of'said face walls and upon inhalation will be moved by external air pressure to contact the other of said face walls, a lever arm located in said compartment having a flat paddle-like disc adapted to be engaged by said flexible sheet when the same is moved by atmospheric pressure when the compartment is emptied by an inhalation, and a normally closed valve. operated by'said movement when the rebreathing compartment is substantially emptied to permit flow of oxygen into and from the rebreathing compartment as long as inhalation continues.

8. A device for administering oxygen at high altitudes comprising a rebreathing compartment formed of a rigid shell having parallel face walls spaced apart a distance which will permit the rebreathing compartment to be worn beneath the coat of a wearer, a flexible sheet held gas-tight aboutits edges adjacent the outer of said walls as Worn, said sheet being folded upon itself so that on exhalation it will contact one of said face walls and upon inhalation will be moved by external air pressure to contact the other of said face walls, a tubular connector member secured to an edge wall of the shell and opening thereinto between said face walls and at the inside of the flexible sheet and extending at right angles to said face walls, said connector being adapted to pass through an opening in the coat of a wearer, a mask and a tube connected therewith and with the tubular member and adapted to extend outside the clothing.

9. A device for administering oxygen and excluding nitrogen, comprising a rigid casing having parallel walls spaced close together to form a shallow laterally expanded chamber adapted to be positioned under an aviators coat, flexible means within the chamber subject to external air pressure forming a sealed reservoir, a mask and a breathing line opening into the reservoir including a rigid connector member extending at right angles to the walls of the casing and adapted to pass through an opening in the aviators coat, and means for supplying oxygen to the reservoir including valve mechanism therein actuated by movements of the flexible means resulting from respiration.

JAY A. HEIDBRINK. 

